Fluid pressure control apparatus



June 23, 1953 R. R. STEVENS FLUID PRESSURE CONTROL APPARATUS Filed Sept. 22. 1948 g INVENTOR. BY Roy R. Stevens ATTORNEY mmw 3m it z g mm 3 #0 N.

Q. kw ,lucsoa Sou Patented June 23, 1953 2,642,969 F'LUIii reassess CONTROL APPARATUS Roy R. Stevens, Westinghouse tion; of Pennsylvania Forest Hills; Pa., assign'or. to Brake Company; a corporat Appucadbfisfepiemiier 22, 194i; s'erai'sasuste "16 Claims (01. 192 12i This invention relates to fluid pressure trol apparatus and more particularly to fluid pressure apparatus for controlling operation of an engine power packagesuch as may be em ployed in rotary oil well drilling equipment;

A powerpa ckage urine-above typemay corn prise a plurality of power units' -sii'ch as a pair of internal combustion engines adaptedto be operably connected to' a multiple speed trans mission for operativeconnection with a draw Works hoisting drum, sand ree1,--rotar y table, etc. The transmission may comprise friction clutches and positive jaw" t peclutches adapt ed to be engaged and isengaged selectively for efiecting respective changes in speed ratiotram input to output of the transmissiorisystem;

It is one objectof the invention to provide fluid pressure control apparatus for controlling operation of the above mentioned engines and for selectively efiectingoperative connection between one or all of said engines and the trans-- mission for driving saine while automatically as= suring synchronism of the power output of the engines when all-are thusemploy'edr It is another object of the inventionto: provide fluid pressure control apparatus for selectively controlling engagement of respective friction and jaw clutches and automatically assuring that the jaw clutclies-may be ngage orv disen gaged onl'y when' the-rotatable parts thereof are turning at sufficiently low speed as-wil'l not cause shockto said-clutehes-a'nd equipment;

Other objects and advantages-will be a'pparen't from the following moi-e detailed 'clescription of the invention.

In the accompanying erawmgmhe single? fig ure is i a diagrammatic view; partly in outline and partly in section of a power: package or: unitembodyingthe invention} Descriptionjustable in accord with position" ofa espectiv governor control lever 3. Lever 3*ls'oper'at1ve1y' connected to a governorshaft" and isadapted for pivotal movement thereabout to and between opposite extreme 1iiiiit position;- Idle and Fullspeed, indicated by dotanddash lines so tit'led in the drawing; f-oradius'ting the' governor device through turn-ingmovem'nt of shaft to effect adjustmentor: the: speed. on the respectiveengine accordingly For adjusting} position-or fever 3; a fi'uid pres sure cylinder device T is provided which com prises a piston B which is oper'ativ'ely connected means of' a piston rod 9 'to said lever. A contro'l spring" m is disposed iir a} spring chamber H at one side of pistonli, arranged to urge said piston the direction of a pressure chamber l2 at its opposite side toward a} rest position in which it is shown the drawing with lever 3 in Idle position. Piston 8' will e'fifect positioning of lever 3-in accord with the' degree of pressure or fluid supplies to the chamb r I": sense th reon to oppose action or spring m1 "Fun speed po sition of lever 3 will correspond to "a certain maii imum pressure of'fl'uid-lfi-chamber l2 and Idle positionto acertain-minimum pressure in said chamber. 7

For effecting" variation pressure of fluid in the respective press'iire chambers 12 in the cyl-" inder devices I and thereby eifecting adjustment of the'speed" o'fienginesl} 2"; selmappmg' control valve devices [5; l6} l1 are provided.-

The self-lapping control valve devices l5, l6,

l1 may be substantially'sim'ilarto a, control valve device disclosed and described ill- Patent No.

2,398,877, issued to A: J. Bent, April 23', 1948,.

and assigned to the assignee of the present appli-cation. SelfJappih'EiCdfitfbl Valve devices Hi,v to sheet variations in pressure I! are operable of fluid respective pipes I8 19' in accord with position-of an operators handle 2-0; while" selflappingc'ontrol fec't variation in pressiurecr fluid in-a' pipe 2| in accord with position ita foot pedal 22. hancll'e's 'i-fl are=movable to and between opposite limit positions corresponding. to 'Idle and Full speed positions of: the governor levers 3 in the engines 'I, 2. Likewise footpeda1-22 may be so positioned also to and between such limit sitions, indicated byi dot and dash lines-so titled. Idle position of handles: 20 and of foot pedal 22 corresponds to -a certain minimum pressure of fluid in respectivewpipes m; I9, 2-], while Full speed" position of-said handles and footpedal correspond to a certain maximum pressure of fluid in these-pipes.- Handles ZIP-will remain in any position to which -theyareymoved, while foot pedal-22 is constantly: urged toward its Idle position by action of a spring 23; A'fiuid pressure supply pipe 24; adapted to be connectedto asourc'e of'fluid under pressure, such as-a' com pressor (not shown), is connected toeach of the self -lapp'ing control valve devices I5, Hi;- II for conveying. fluid under pressure-thereto.

Pipes l8; H are connectedcommon to a pipe 25 bywaSt of a. double check valve 25 in The games such a manner that pressure of fluid in said pipe 25 may be varied either by operation of valve devices l or l6 independently, or a pressure at some value may be established and held therein by fixing a position of handle in device l5 "and effecting variation in pressure above that value by adjusting position of foot pedal 22 in device l6, thus affording flexibility of operation.

Pipe 25 is constantly connected to the pressure chamber l2 in the cylinder device 1 on the engine 2, and according to a feature of the invention, is adapted to be connected to the corresponding chamber in cylinder device 1 on engine by way of a pipe 26 and a relay valve device 21, so that variation in pressure of fluid in pipe 25 will effect simultaneous synchronous adjustment of speed on both engines 2 through operation of either of the valve devices |5, |6. Relay valve device 21 is also operable to disconnect pipe 25 from pipe 26 and to connect the latter pipe to the pipe |9 so that the speed of engine I will then be under the control of valve device H, with the speed of engine 2 under control of either or both of valve devices The relay valve device 21 may be of usual construction comprising a casing in which is clamped a diaphragm 34. At one side of diaphragm 34 there is a control ressure chamber 35 adapted to be supplied with fluid under pressure for urging said diaphragm to deflect in the direction of a chamber 36 at its opposite side. Chamber 36 is connected to a port 31 opening outwardly through the casing. A control spring 38 is disposed in chamber 36 adapted and arranged to urge diaphragm 34 in the direction of control chamber 35 toward its rest position in contact with a shoulder 39 formed in the casing, in which position it is shown in the drawing. A stem 40 is secured for reciprocable movement with deflection of diaphragm 34 for actuating two valves 4|, 42. Stem 40 projects through chamber 36 and is slidably guided in a bore which opens through a partition 44 dividing chamber 36 from a chamber 45. The projecting end of stem 40 has an operating connection with valve 4| which i disposed in the chamber 45. By reciprocable movement of stem 49, valve 4| is brought into and out of seating engagement with a valve seat 46 formed at one end of a bore extending through a partition 41 which separates the chamber from a chamber 49. The valve 42 is disposed in a chamber 50 and arranged to cooperate with a seat 5| formed at one end of a bore extending through a partition 52 which separates chamber 49 from the chamber 50. Valves 4|, 42 ar secured to respective fluted stems slidably mounted in the bore extending through partitions 41, 52. A bias spring 53 is arranged to urge valve 42 to a seated position closing chamber 50 from chamber 49, while, through contact with the fluted stems, valve 4| is at the same time urged away from seat 46, opening chamber 45 to the chamber 49.

When fluid under pressure is supplied to the control chamber 35 in relay valve device 21, through consequent deflection of diaphragm 34 and thereby movement of stem 40, the valve 4| is seated and the valve 42 is unseated. Chamber 49 is thus closed off from chamber 45 and open to chamber 50.

When fluid under pressure is released from control chamber 35, the relay valve device will assume the position in which it is shown in the drawing with valve 42 seated and .valve. 4| unseated. At this time, chamber 49 is open to chamber 45 and closed to chamber 50.

Pipe I9 i connected to chamber 45 in relay valve device 21, pipe 25 is connected to chamber 59 in said device and pipe 26 is connected to the chamber 49 in said device. A control valve device 55 is arranged to control supply and release of fluid under pressure to and from the control chamber 35 in relay valve device 21 by way of a pipe 56 connected to said chamber.

Valv device 55 may comprise a casing having a chamber 51, a supply opening 58 at one end connected to the supply pipe 24, an exhaust opening or openings 59 open to atmosphere, and a delivery opening 60 intermediate openings 58, 59 and connected to the pipe 56. A double faced valve 6| is disposed in chamber 51 arranged to cooperate with oppositely disposed seats 62, 63 encircling openings 59, 58, respectively, to control communication between chamber 51 and said openings. Valve 6| is urged toward a position seated on seat 62 by action of a compression spring 64. A stem 65 is attached to valve 6| through which said valve may be actuated. A

cam 66, disposed within a cap 61 secured to the casing, is arranged to be turned about a pivotal connection with said cap for actuating stem 65. An operators handle 68 is attached to cam 66 for efiecting turning movement of same. Handle 68 extends outwardly through a slot formed in the cap 61, the opposite ends of which slot may serve to define two positions of the handle, Compound and Individual, indicated in the drawing by dot and dash lines so titled.

In Individual position of handle 68, in which it is shown in the drawing, valve 6| is seated by cam 66 on seat 63 with pipe 24 closed from chamber 51 and pipe 56 open to atmosphere via said chamber and the ports 59. Relay valve devic 21 is therefore positioned as shown in the drawing with the pipe 26 consequently connected to pipe 19 so that the speed of engines I, 2 may be controlled individually, as will be appreciated from previous description.

When handle 66 in device 55 is moved from Individual to Compound position, valve 6| seats by spring 64 on seat 62, closing ports 59 and opening port 58. Fluid under pressure from pipe 24 will then flow into pipe 56 to relay valve device 21 which will respond to disconnect pipe l9 from pipe 26 and connect the latter pipe to pipe 25 so that the speed of both engines I, 2 may be controlled simultaneously in synchronism .by operation of either or both valve devices |5,

|6, as previously described.

Engine 2 is adapted and arranged to drive a shaft 16, and thereby to drive an input shaft 1| of a variable speed transmission 12 through the medium of sprocket wheels 13, '14, secured for rotation with shafts 10, 1|, respectively, and a chain 15.

Engine is adapted and arranged to drive a shaft 16 which may be provided with a pulley 11 or the like to allow for operative connection to a mud pump (not shown), for example, such as is employed in rotary drilling rig equipment. Shaft 16 is arranged to be connected to the shaft 10 of engine 2 through a sprocket wheel 18 secured to shaft 16, a chain 19, a sprocket wheel secured to a shaft 8|, a friction clutch 82, a sprocket wheel 83, a chain 84, and a sprocket wheel secured for rotation with the shaft 10.

One friction element 86 of the friction clutch 82 is secured to the sprocket wheel 83. Sprocket wheel 83 and friction element .86 are free to rotate on shaftiit which extends therethrtough A second friction. element, 81; of clutch,,82-, disposed opposite and parallelto. element 8.6; in; its disengaged position in which itis shown in the drawing, is securedforrotation withshait, and is slidable axially thereof; into engagement. withrelement 86 for transmitting torque. thereto from.

shaft ii Friction clutch 82 isarranged toibetoperated by a fluid pressure clutch actuator fl'fl, through a lever 89 which is fulcnumedfintermediate its ends on a fixedpin 90. I

end of lever 89- providessforloperative-connection with the friction element 8'! of clutch 82; an.- integral sleeve: in which is formedanannular groove Bl, said element being provided'lfor receiving said yoke. The;oppositeend of:lever8.9 maybe connected through lallink 921-190 one end of.

a rod 93 of the clutchactuator; 8,8. Actuator.- 8.8 comprises a casingpontaining; a piston 3.4 which is connected to the rod 93... At one lside of piston EM there is a chamber: 95 connectedjto the pipe.

56, while at its opposite side thcre,is,=a spring chamber to which is constantly; open to; the

atmosphere. A release; spring 9 is disposed. inv chamber 9% arranged to urge pistonssdi in the.

direction of chamber. 95 toward its restoposition seated on an annular shoulder: formed.,ir1,the.v

casing, in which position it is shown inl the. draw ing. In rest position.ofpistontfll cliitchdlis in its release position with elementlfilldisengaged When fluid Y under press are, is; supplied to chamber 9.5, piston 941s. causedto.

from element "86.

move in the direction of chamber; 9 6; against action of spring and levertil it causes engagementtofl element Ti with element,tfiinfrictioniclutch 8;2forlcou pling shaft 3i 83, t and chain 84. When fiuidundenpressure is subsequently vented from cliam-heriiiilin actue ator 855, spring 91 returns. piston94'to restposi tion and causes clutch 82to; disengage.

According to a feature of the invention, engage ment of the clutch '82 iseffectedjto.connectlthe,

shaft 75 of engine l to the shaft Jfitof engine?r through supply of .fiuid under pressurete pipe 56, at the same time thatv the speedhofgboth engines i, 2.is broughtunder thecon-trol-oe con trol valve devices l5;and,-l6 andgisthereby, syn-v chronized. Conversely, disen t fiment of =clu-tch $2 is effected automatically, through releasee fluid under pressure in pipe 56,, at .thersarne time that speed of the engines I, v 2-arerenderedeon-e trollable individuallythrough :operationwofzvalve devices iii, it and the valvedevi-cee 11,- refines: tively.

By means of such an arrangement; arr operator of the equipment maycom-pound or render :inde: pendent both control of and output of-the-engines i, 2 merely by positioninghandle fia in valve devicett.

An output shaft J60 is provided :the -,trans m-isesion '52 to which-power supplied.togdrive-itszinput shaft it maybe transmitted fortoperative connection with devices; to ,-be ;operated .zor driven. The output shaftillil is provided with sprocket wheels mi, H12, 13 secured for rotation. there-- with for operative connectionto .a l-rotary; table, sand reel, and draw-workshoistingdrum (none of which are shown) on a rotary well drilling rig, for example. It is understood that in" such an application clutches wouldbe employed in the driving connection with the various devicesxto provide for necessary flexibilitypand. theirg'independent operation;

A yokefattachedi to i one,

to shaft I0..through sprocketwheelt.

The-:variablespeed transmission: 72 may byway of example be adapted and. arranged oprovide speed of rotation of its;

four different. ratios of input shaft'll to speedgofrotation: ofits output shaft m9;

Transmission 12. ate-shaft other of may comprisean. intermediadapted' to, be driven :by inputshaft 1;]. I05, ously, described and. are. operable in similar fashion by means of respective fluid pressure clutch actuators z I 0% I 09, respectively; whicli= aresimilar to thel-actuator'fiiic Clutch lllfij-is engaged: through alever I 10- whenlfl'uidiunder pressureis supplied to actuatorv 08; .and the. clutch IUTisengaged througha lever lfll whenfiuid under pressure issuppli'ed to the. actuatorfllflflr Conversely, clutches H16;

1 69, respectively.

In rashionlsimilar to that describeddntregard to operation of engaged, shaftl'liiis. operatively connected? toa sprocket wheel i201 whichiis in turnconn'ected through a chain I21 andcsprocketlwheell42.2 to

the shaft H15 Sprocket wheel I201 13. journaied ontolshaft. 71' so that when clutch Hi6? is disengaged saidsh-aft free. to turn therein relative thereto, while sprocketwheelf lfl'issecured for rotation .withshaft. I 0'5 Similarly, in engagement; clutch [6T operativel'y connects shaft. Tl f to-l-a.,.sprocket whee1' i23 andthrough a chain, l24'and' sprocket wheel I25, to the shaft [05L Sprocket wheel. l25is secured tolshaftIll BFffor rotation therewith while sprocket wheel sprocket wheel, rotate one. relative to the other.

In operation, Where input shaft speed of rotation, through selective'engagement of clutch M81 or clutch I01 the shaft caused torotate at a speed'lower higher than the speed of rotation or" a speed of shaft-'11;

according to the. ratio of diameters of the sprocket wheel I 20 to sprocket wheel I22 1 andlojf sprocket wheel [23 to sprocket wh'eel I25." For sake of i1lustrati'on',,as shown sprocket .wh'eel I29 may be of lesser diameter'than when clutch I0! is low speed?" be referred To. control operation of friction" clutches Int;

Hi! a control valve'device'wfl' is provided. Control Ivalve device. ISOQmaybesubstantiallyiof the type disclosedl and. described in detail in U; 3'.

Letters vPatent No. 2,329 I142, issued to Rankin J. Bushet .al.,. Sep t.l 21, 1943, .andlassigned' to thelassignee. of 'the present application. Valve device I3B-is .of the :self-lappingtype andlcomprises an operatorslleverlal which is movable in one direction ,out of a Neutral position. in

which it is shown in the .drawing toward a Low speed! position, indicated b'ybadot andw dashllihe I 05 arrangedito-be driven atone' or. the two operating speeds throughv selective engagementof two friction. clutches H16}; H11- Clutches- IEIT may be, similarv to the clutch 82, previ it? arezdi'sengagedi when fluid under pressure.islventedifromr actuators Hi8,

clutch. 82", when clutch lift"- is I231 is' journaled onto. the shaft 7'! 1 so thatfwhen. clutch I OTis disengaged said" I25 and lsaidfshaft Tl arefree'to" TI is being. driven by one or both of'engines I; 2"at a certain I05 may be the drawing;

Whichsh-aft H turns, while conversely; sprocket wheelv will turn at a faster For this reason,,friction clutch I 06' 7 so titled, to effect increase in pressure of fluid in a pipe I32 connected to the pressure chamber 85 of actuator I08 for engaging the Low speed" friction clutch I08. Lever I3I is movable in the opposite direction out of Neutral position toward a High speed position for effecting increase in pressure of fluid in a pipe I33 connected to the pressure chamber 95 in the actuator I09 for effecting engagement of the High speed friction clutch I01. In Neutral position of lever I3I, both pipes I32, I33 are vented to atmosphere via a pipe I34 and both the clutches I05, I01 are disengaged. In moving lever I3I out of Neutral in either direction toward either Low speed or toward High speed position, the characteristics of valve device I30 are such that pressure of fluid in pipe I32 or I33 will be increased gradually during the major portion of lever movement with arapid increase in pressure effected during the final portion thereof as said lever nears one or the other of its opposite extreme limit positions. Such action assures a gentle initial engagement of the friction clutches I00, I01 and thus prevents excessive wear or damage to said clutches and equipment which otherwise might occur were such initial engagement too rapid and severe.

As a source of supply of fluid under pressure for the valve device I30, same is adapted to be connected via a pipe I35 and relay valve device I38 to the supply pipe 24.

The multiple speed transmission also comprises two position jaw type clutches I31, I38 which are operable selectively to effect operating connection between the intermediate shaft I05 and the output shaft I through one or the other of two pairs of sprocket and wheel and chain arrangements of different gear ratios." Thus the output shaft I00 may be driven at two different speeds relative to the shaft I05, and since shaft I may be driven at two different speeds relative to speed of input shaft 1I, four different speeds of the output shaft I00 relative to speed of said input shaft 1I may be obtained.

Such an arrangement may comprise one pair of sprocket wheels I4I, I42 connected by a chain I43, with sprocket wheel I4I secured for rotation with shaft I05 and sprocket wheel I42 journaled onto shaft I00, and a second pair of sprocket wheels I44, I45 connected by a chain I46, with the former secured to rotate with shaft I05 and the latter journaled onto shaft I00. The ratio of the diameters of sprocket wheels I4l, I42 and of sprocket wheels I44, I45 may be of any desirvalues to obtain two speeds of operation of shaft I08, which, for sake of illustration, may be referred to as Low speed and High speed, respectively. For this reason the clutch I31 may at times be referred to hereinafter as the Low speed jaw clutch and the clutch I38, as the High speed jaw clutch,

The jaw clutches I31, I38 may be of the usual type comprising jaws I50 attached to opposite ends of a clutch element I40 common to both of said clutches, which jaws are adapted to mesh with corresponding jaws I5I formed in integral portions of the sprocket wheels I42, I45, respectively. Clutch element I40 may be keyed to shaft :80 to allow for its axial movement and for transmitting torque thereto from one or the other of the sprocket wheels I42 or I45 when clutch I31 or I38 is engaged. In a neutral position of clutch element I40, in which it is shown in the drawing with both clutches I31, I38 disengaged, even though shaft I05 and thereby sprocket wheels I42, I45 may be rotating, shaft I00 will be idle.

For actuating the clutch element I40 to engage or disengage clutches I31, I38, a fluid pressure clutch actuator I55 is employed which comprises a cylindrical casing I56 having a piston I51 slidably disposed therein. At opposite sides of piston I51 are respective pressure chambers I58, I59 adapted to be supplied with fluid under pressure selectively for causing said piston to move within the casing in one direction or the other. Compression springs IEO, IGI are disposed in chambers I58, I59, respectively, arranged to urge piston I51 in the direction of its neutral position intermediate opposite ends of the casing, in which position it is shown in the drawing. Piston I51 is operatively connected to the clutch element I40 through a piston rod I82, a link I63, and a lever I54. Lever I04 is fulcrumed intermediate its ends to a fixed pin I65 and its one end is provided with a yoke which fits in an annular groove formed in clutch I40, while its opposite end is connected to link I03. When fluid under pressure is supplied to chamber I58 in actuator I55, the clutch element I40 is brought into engagement with sprocket wheel I42 for thereby driving output shaft I00 at Low speed, while if fluid under pressure is supplied to chamber I59 in said actuator, said clutch element engages sprocket wheel I45 to engage clutch I38 for driving shaft I00 at High speed, relative one to the other. It will be appreciated that when fluid under pressure is supplied to one of chambers I58, I58 to effect an engagement of clutch I40, the other of said chambers will be vented to atmosphere. Upon venting of fluid under pressure from both chambers I58, I59, springs I68, I6I will act to return both clutch I40 and piston I51 to neutral.

To control engagement and disengagement of the jaw clutches I31, I38 a control valve device I10, which is similar to control valve device I30, is provided. Control valve device I10 is operable, by means of handle I3I when moved out of its Neutral position to its Low speed position, to effect a controlled build-up of pressure of fluid in a pipe I1I which is adapted to be connected to pressure chamber I58 in jaw clutch actuator I55 by way of an interlock valve device I12, a pipe I13, an interlock valve device I14 and a pipe I15, for effecting engagement of the Low speed jaw clutch I31. To furnish fluid under pressure for such operation, the valve device I10 has a connection with the supply pipe 24. When handle I3I of the control valve device I10 is moved in the opposite direction out of Neutral to its High speed position, a controlled build-up of pressure of fluid is provided in a pipe I15, which is adapted to be connected to the pressure chamber I59 in jaw clutch actuator I55 by way of an interlock valve device I11, a pipe I18, an interlock valve device I19 and a pipe I80, for effecting engagement of the High speed jaw clutch I30. In Neutral position of the handle I3I of control valve device I10 both pipes I1I, I18 are vented to atmosphere by way of pipe I34. When fluid under pressure is supplied to one of pipes I1 I, I16 from device I10, the other of said pipes is vented by said device to atmosphere via pipe I34.

The control apparatus further comprises relay valve devices 85, I83, double check valves I81, 188, I89, a brake cylinder I30, a governor valve device ISI, and a speed governor I92.

All of the relay valve devices I30, I12, I11, I14, I13, H35 and I are similar to the relay valve device 21 previously described. Each of these e t tes other. relay valve: devices is" shown: in" the draw ing in outline and for. description thereof'irefer ence may bemade to description of device 21. For sake of simplicity in following'thei'r. opera-- tion in subsequent description, a solid line I95;

shown. in outline, since. same are well known inv the art. Each is operable. to. estbali'sh connectatable governor head 222 meshingiengagernentwith the teeth on gear. 2| 6.

while its opposite. end. is operably connected to a bell crank likeilever. 2I8in the governor I92.

The speed governor. I92 may comprise a roadapted to be rotated by the output shaft I of" the transmission 12 through. gears 222 pivotally carries two oppositely arranged bell cranks" 225 having" governor weights 226 at. their tion between one of. two opposite inlets. upon its pressurization, and an outlet, in .the usual man, ner, so that said. outletwillbe pressurized when either of said inlets is pressurizedand..will.be

vented to atmosphere only when both inlets are.

so vented.

The brake cylinder I90 is. provided as. means.

for effecting retardation of the shaft I05 and.

thereby sprocket wheels I42, M5. in the. transmission I2 to allow for safe engagement and'di's-- engagement of. the jaw. clutches I37, [38. Brake cylinder I90 may be of any suitable. construction. but for sake of. illustration isv shovvnfsimply as comprising a hollow cylindrical casing 200-in which is slidably disposed a piston 201 having the. usual pressure chamber 202 at its oneside and a spring chamber 202a. at its opposite side, whichlatter chamber is constantly open. to atmosphere. A brake shoe 293 is operably connected to piston 220i through. a piston rod 20.4.ior engagement witha brake drum-1.2.05 which is. secured for rotation withthe transmission shaft 405. Fluidunder pressure supplied to the pres-y sure chamber 262. effects engagementot shoe. 203 with drum 205 throughmovement of piston .201, and a compression spring 206 is arranged in chamber 2020 to urge said piston and brake shoe to a brake release or rest position in which they are shown in the drawin The governor valve device I 9I may comprise a hollow casing 29! having a chamber 208 therein which is disposed a valve 209. arranged to contrel communication between said chamber and exhaust ports 2i 0 open toatmosphere. Valve. 2% is urged toward-its'closed positionin which.

itis shown in the drawingseated on an annular rib 21 I encircling ports 2I0 by a compression. spring 212. A stem 2J3 issecured. to valve 209 through which said valve may be caused to move away from rib 2| I to open chamber 208 to atmosphere by way ofports 2I0. -A.cam 2M is disposed outside the governor valve device I9! for actuating stem 2I3 to open'and close valve 209. Cam 214 is secured for turning movement. about a pin or shaft 2I5 which. is in turn secured. to a,

gear 2I6 through which said turning movement may be efiected. Cam 2 I4 is so adaptedland are ranged that in turning in a clockwise direction with shaft 2I5, as viewed. in the drawing, stem.

2I3 will be displaced inwardly of casing. to Upon subsequent turning move-, ment of cam 2 in the opposite direction. spring. 209 to or toward its closed open valve 209.

M2 will urge valve. position.

Arack element2l1, arranged to be actuated by the speed governor I92, is provided. for effect ing turning movement of gear 2I6'. one end of rack element 211' is provided with teeth for outer-ends, while their. adjacent inner ends engage a' collar 22! secured to a longitudinally movable adjusting. rod 228'. A governor control spring 229 acts against the rod 220 in opposition to centrifugal action of hell cranks 225' on collar 22'! upon rotation of head 222 by the shaft I00. A cam 230, pivotally connected to a. fixed pin2 3| is operable upon turningmovement about said pin to. increase anddecrease pressure. of

spring. 222. as desired;

The adjustingrod 22 3' is provided with an operating pin232 disposed in a groove formed in one end of the lever 2I8 connected to rack ele-,

ment 2 I7. Lever 2I8, is pivotally connected to a fixedpin 2.33, so that axial movement of. rod 228 will rock lever. 2I 8 and cause axial movement oi. the. rack element 211'.

When shaft I00 is stopped or substantially so, the governor I92, lever 2'18, rack element 2H, and governor valve I 9| willbe in the position in which they are. shownin the drawing. When shaft I00 is turning; above a certain minimum. speed, which may be substantially zero, through resultant turning movement of governor head 2221' and centrifugal action of. cranks 225 acting,

on. collar22l, theadjustingrod. 22.8 is caused. to move upwardly, as viewed in the drawing, and.

rocle lever.2.lB. ina. clockwise directionabout pin,

233 and'through rack element 2I'I, gear 2I-6', cam

2M and stem 2| 3 cause valve 209 in governor valve device I9I to open. Once theshaft. I00

stops turning, or substantially so, in response to.

the reduced centrifugaliaction of cranks 225 acting. on collar 221, thespring 229 moves rod 228v downwardly, asrviewed in thedrawing, and rocks lever 2I8 in a counterclockwise direction about pin 233 and through rack element 2I1, gear 2I6 and cam 214' allows: valve. 2.09 to close. 7

Referring now torthe' relay valve device I36, its chamber 49 is connected to pipe I35 its chamber 50 is connected to a pipe 235 which is open to atmosphere, its chamber'45 has a connection with the pipe-24; with a choke 236 inserted thereinforreasons which-will become obvious'herein:

after, and its control chamber 35 is'connected toa pipe 23'! which in turn is connected to pressure chamber 292m brake cylinder I90, to chamber 49 in relay valve device I85, andto chamber '50 in relay valve device I86. A pipe 238 has a cori- Y nection with the pipe'231 and a choke 238' is inserted'in this connection for reasons which will be pointed out hereinafter. nected to the chamber 208 in the governor valve device HM and to the'control chamber 35 in they relay valve device' I06.

In relay valve device In, chamber 50' is connected to the pipe III, its chamber 49- is connected to the pipe-I13, chamber 45 is connected to a pipe 195" which is open to atmosphere and itscontrol chamber 35 is connected viaa pipe I to the outlet of double check; valve I88, one inlet of. which is connected to said pipe I13 and the other -offwhich is connected to apipe 239 which alsozhas a connection to one of-the'inletsofdouble check valve: I89.

Pipe "3 has-one" connection with one inlet of 223 and a shaft 224. The head Pipe 238*is also conthe double check valve I81 and a connection with the chamber 45 in the relay valve device I14. Also in relay valve device I14, chamber 49 is connected to the pipe I15 which also has a connection with control chamber 35 as well as the previously mentioned connection with chamber I58 in actuator I55, chamber 59 is connected to supply pipe 24, and chamber 36, rather than being open to atmosphere as in relay valve device 21, is connected to the pipe 239 which has a connection with the corresponding chamber in relay valve device I19 and a connectionwith chamber 49 in relay valve device I86, as Well as its previously mentioned connection with double check valves I88, I89.

In relay valve device I11, chamber 45 is connected to a pipe 249 which is open to atmosphere, chamber 59 is connected to the pipe I16, chamber 49 is connected to the pipe I19, and control chamber 95 i connected via a pipe I89 to the outlet of double check valve I89 whose opposite inlets are connected to pipes I18 and 239, respectively.

Pipe I18 also has a connection with the other 'inlet of double check valve I81 and a connection with chamber 45 in relay valve device I18. Also in relay valve device I19, chamber 59 is connected to the pipe 24 and chamber 49 is connected to the pipe I89, which, in addition to its connection with chamber I59 in actuator I55, has a connection with control chamber 35 in said device I19. All other chambers in relay valve device I19 are connected as previously described.

In relay valve device I85, chamber 45 is connected to supply pipe 24, chamber 59 is connected to a pipe 24I open to atmosphere by way of a choke 242, and control chamber 35 is connected to the outlet of double check valve I81 by a pipe 242'.

In relay valve device I88, the chamber 45 is connected to a pipe 243 which is open to atmosphere by way of a choke 244.

In relay valve devices I38, I12, I85 and I86, their respective chambers 36 are open to atmosphere by way of a port I1 as in the relay valve device 21.

Operation of portion of control apparatus for controlling multiple clutch operation In operation, assume that the supply pipe 24 is charged with fluid under pressure and that one or both engines I, 2 are running and driving the input shaft H of the multiple speed transmission at some particular speed. Control of speed of engines I, 2 was previously described, and, since said speed does not necessarily affect operation of the transmission 12, said description will not be repeated, so for subsequent description of operation of the control of the transmission 12, assume that the speed of shaft 1I remains constant although it should be understood that same may be increased or decreased as desired by regulating the speed of the driving motor or motors through manipulation of control valve devices I5, I6 and/or I1.

Assume further, that handles I3I of control valve devices I39 and I19, for controlling operation of friction clutches I98, I91 and jaw clutches I31, I38, respectively, are in their Neutral positions. Pipes I32, I33 are vented to atmosphere by way of the control valve device I39, so that both friction clutches I86, I91 are disengaged, as will be understood from previous description. As a consequence, there is yet no driving connection between the input shaft 1 I, which is rotating, and

the intermediate shaft I95, which is yet to turn so that sprocket wheels I29, I22, I23, I25, I4I. I42, I44, I45 and shaft I99 are idle. The valve 299 in governor valve device I9I is closed, since shaft I99 is not turning, as will be appreciated from previous description. Pipes I1I, I19 are both vented to atmosphere by way of the control valve device I19.

Relay valve device I12, I11, operated by fluid under pressure from the relay valve device I88,

for reasons which will hereinafter be brought out, are positioned to connect pipes I13, I18 to the pipes I1I, I16, respectively, and are thereby vented to atmosphere.

The control chamber 35 in relay valve device I is thus vented to atmosphere by way of pipe 242', double check valve I81, and pipes I13, I18, so that relay valve device I85 is positioned to connect, via its communication I95, the supply pipe 24 to the pipe 231. Pipe 231 is thus charged as is the chamber 292 in the brake cylinder device I99 for applying the brake on shaft I and the control chamber 35 in the relay valve device I36 for cutting off supply of fluid under pressure to control valve device I39 and venting pipe I35 to atmosphere, and since the governor valve device I9I is in its closed position, the control chamber 35 inthe relay valve device I88 will be charged with fluid under pressure by way of pipe 238 and choke 238. The relay valve device I86 thus is positioned to connect pipe 231 via its communication I96 to pipe 239 which is therefore also charged with fluid under pressure, as, consequently, are the respective chambers 38 in relay valve devices I14, I 19 and the control chambers 35 in the relay valve devices I12, I11 by way of double check valves I68, I89 and pipes I88, I89 as previously indicated.

Pressure of fluid in chambers 36 in the relay valve devices I14, I19, respectively, condition said devices to connect the pipes I15, I89 by way of their communications I95, to the pipes I13, I18, respectively, and thereby to atmosphere. The control chambers 35 in the respective relay valve devices I14, I19 are now open to atmosphere by Way of pipes I15, I89, as are chambers I89, I9I in the fluid pressure clutch actuator I55, so that said actuator is now in its neutral position, in which it is shown in the drawing, with both jaw clutches I31, I38 disengaged.

Assume now that it is desired to engage the low speed jaw clutch I31. The operator may then move the handle I3I of the control valve device I19 to Low speed position and thereby efiect 4 supply of fluid under pressure from the supply pipe 24 to the pipe I1I while maintaining the pipe I16 vented to atmosphere.

Fluid under pressure thus supplied to pipe I1I will flow through communication I96 in the relay valve device I12 into pipe I13, and from pipe I13 into the upper inlet of double check valve I88, the opposite inlet of which is yet charged with fluid under pressure from pipe 238, into and through the double check valve I81 to the control chamber of the relay valve device I 85 via pipe 242', and through the communication I95 in the relay valve device I14 into the pipe I15 to the control chamber of said relay valve device I14 and to the chamber I99 in the clutch actuator I55. At this time, chamber I59 in clutch actuator I55 will remain open to atmosphere by way of pipe I89, communication I95 in the relay valve device I19, the pipe I18, communication I96 in the relay valve device I11, pipe I16, and the control valve device I19. The

adapts clutch actuator I55 will-then respond to engage the low speed jaw clutch ItL-thereby efieotin g a drive connection between the intermediate shaft Hi and the output shaft Illt.

At the same time, fluid under pressure thus supplied to the control chamber 35 of the relay Valve device I535 renders said device responsive to vent the pipe 237 to atmosphere by way of its communication I -l3, the pipe 2 3i and choke 242. Fluid under pressure from the chamber 202 in the brake cylinder Itd, fromthe control chamher in the relay valve device Itfi, via pipe 238 and choke 238, and from the control chamber in the relay valve device I36, thus flows by way of pipe 237 to atmosphere. The brake on shaft I 35 is thus released and therelay valvedevice I36 responds to connect supply pipe 2 4 to the pipe I35 hence to the control valve device I36 to allow same to be effective; it being however assumed in the present description the said control valve device I36 is in neutral position causing disengagement of both friction clutches its, fill.

In response to venting of fluid under pressure from its control chamber, the relay valve de vice I86 now connects the pipe 239 to atmosphere by way of its communication I85, pipe 243 and the choke 24d. Fluid under pressure in chamber 35' in the relay valve devices We, I'll. is now vented to atmosphere by way of pipe 239, as well as is fluid under pressurein the control chamber 35 in the relay device ill by way of pipe ltd and the double checlrva'lve I89 since the opposite inlet of said double check valve is at the time vented to atmosphere by way of pipe Fit. The control chamber 35 in the relay valve device 32, however, remains charged with fluid under pressure from pipe I'I-E by way of the, double check valve" I t8 and the pipe I88.

In response to venting of fluid under pressure from its chamber 35, the relay valvedevice I'M will respond to previous pressurization of its control chamber 35 to establish connection be tween the supply pipe 2 2 via communication I96 and the pipe I and thereby maintain chamber l I58 in jaw clutch actuator 555' charged with fluid under pressure. At this time, since its control chamber 35 is now void of fluid under pressure, the relay valve device I'I9 remains positioned as before even though fluid under pressure has been vented from its chamber 35, so that pipe I Bil, hence chamber I59, remains connected to the pipe I I8 and. to atmosphere. Venting of fluid under pressure from the control chamber in the relay valve device Ill renders said device responsive to connect the pipe I18 to atmosphere by way of its communication I95 and the pipe its rather than by way of communication I95, pipe Il and the control valve device I'It as previously, for reasons which will hereinafter become obvious.

The purpose or purposes of chokes 236, 253", 252 and 2% hereinafter will be set forth.

If it is now desired to return the jaw clutch actuator I55 to its neutral position for effecting disengagement of the low speed jaw clutch I37 prior to subsequent engagement of the high speed jaw clutch I 3%, for example, or for any other reason, the operators handle I3I on the control valve device Ilt may be moved fromits Low speed position to its neutral position, thereby venting fluid under pressure from the previously charged pipe I?! while the pipe I16 remains vented.

Pipe I13 is now vented to atmosphere by way orcommnnicatlon 196 i n relay va1ve' device I 72 andthe pipe IH. l/Tent-ing of pipe I13 allows leaseofrfluid 11nd. ,r pressure from the control chamber :inYth e relay valve device I12 by way of pipe I88 and the double check valve I88 as well as from the corresponding control chamber {the relay valve device I85 by way of the pipe 242" and the double check valve 1-87. At'this time, pipe-I is disconnected from pipe I13 and connected to the supply pipe 2d through the relay valve device I14 as previously described, so that said pipe -I7-5 will remain charged with fluid under pressure.

Release oflfluid under pressure in the control chamber of the relay valve device I12, conditions said deviceto disconnect pipe 113 from the now vented pipe Ill and to connect said pipe I'It directly to atmosphere via communication ['95 pipe 195. Bysuch an arrangement, the status o @1118 :II- --may not be changed until certain operations have been performed for reasons which will hereinafter become obvious.

At the same time, vfluid under pressure re leased from the control chamber of the relay valve device I85 renders said device responsive to disconnectth'e-pipe 237 from the pipe Edi to atmosphereand to connect said pipe 23? to the supply pipe 24- by establishment of communication +95. Fluid under pressure is thus supplied to the chamber 2-02 in the brake cylinder device I 'for applying a braking force to shaft I05 (which is not-yetturning since the friction clutches I06; 107 are disengaged), to the control chamber in the relay valve device I36 for again disconnecting pipe I35 from the supply pipe E i and opening said pipe I3'5 to atmosphere to render control valve device I 30 ineffective, and to the controllehamber of the relay valve device I 36 by way of pipe 23 and choke 231%, since the governor valve device IB-I is still in its closed position.

g In response to. supply of fluid under pressure to its control chamber, the relay valve device I fifi-effccts connection between the now charged pipe 231 and the pe 239 by establishment of its communication 1%. Fluid under pressure then flows from-pipe 23 into the pipe 233 to the =-controlchamber 3 5 in each of relay valve devices I72, ll'l by way of double check valves I38, I89 and-the'respective pipes I38, and

simultaneously to the chamber 36 in each of the relay valve devices H4, 179.

"In response. to supplyof. fluid under pressure to their control chambers, the relay "valve device III-2' establishes its communication I66 to connect pipe I'I3- to pipe ;I 'I'I, thence to atmosphere via control valve device I10; and the relay valve de vice I TI] establishes its corresponding communication I96 'thusconnecting pipe 118 to pipe I'it and toatmosphereby way of the control valve device 110.

With-fluid under pressure thus applied. to its chamber. 36, sinceits control chamber 35 is void offluid under pressure; the-relay. valve device I19 remains: inlits position establishing com munication ;I9s5 connecting the pipe I86, hence chamber. JE'BJi-n actuator I515; to the pipe I Ill and thereby to. atmosphere. In the relay valve deviceIM, with-supplyof fluid under pressure to chamber 3&6 the. effect of fluid under pressure in the: control chamberfifi is nullified'and the sprin 33 returns said: device to its position disestablish= ing communication I96 and establishing communication 1-9.5, thus disconnecting pipe H5 from the supply. pipe 2.4" and connecting saidv pipe I15 to the pipe I13 open to atmosphere. Fluid under pressure then flows from the chamber I58 in the actuator I55 by way of the pipe I15, the relay valve device I14, pipe I13, relay valve device I12, the pipe I1I and the control valve device I10 to atmosphere. In response to release of fluid under pressure from its chamber I58, the jaw clutch actuator I55 returns to its neutral position through action of springs I60, I6I, thereby disengaging the low speed jaw clutch I31.

Now assume that it is desired to engage the high speed jaw clutch I38, the operator then moves the handle I3I on the jaw clutch control valve device I10 from its Neutral position to its High speed position, thereby effecting supply of fluid under pressure to the pipe I18 and venting of the pipe I1 I.

Fluid under pressure thus supplied to the pipe I16 flows by way of communication I95 in the relay valve device I11 into the pipe I18 to one inlet of double check valve I89, the opposite inlet of which is now charged with fluid under pressure from the pipe 239, to the control chamber of the relay valve device I85 via double check valve I81 and pipe 242 and to the chamber I59 in the jaw clutch actuator I55 by way of communication I95 in the relay valve device I19 and the pipe I80. At the same time, the chamber I59 in the jaw clutch actuator I55 remains open to atmosphere by way of communication I95 in the relay valve device I14, pipe I13, communication I96 in the relay valve device I12, pipe I1 I and the control valve device I10.

Fluid under pressure thus supplied to the chamber I59 in the jaw clutch actuator 255 causes movement of piston I51 to efiect engagement of the high speed jaw clutch I36 through actuation of rod I62, link I63, and lever I64. Upon pressurization of pipe I80, the control chamber 35 of the relay valve device I19 becomes charged with fluid under pressure but is at this time prevented from afiecting position of said device since its chamber 36 is yet also so charged.

At the same time that the high speed jaw clutch I38 is thus engaged, fluid under pressure supplied to the control chamber of the relay valve device I85 renders said device responsive to effect venting of the pipe 231 to atmosphere by way of its communication I95, the pipe MI and choke 242 to efiect release of the brake on shaft I through venting of fluid under pressure from chamber 202 in brake cylinder device I90 and to render the friction clutch control valve device I30 effective, through release of fluid under pressure from the control chamber of the relay valve device I36 which responds to connect the pipe I35 to the pipe 24. The action of choke 242 is to so restrict release of fluid under pressure from the pipe 231 as to allow sufficient time for engagement of the jaw clutch before the brake on shaft I05 is released and before the friction clutch control valve device I30 is rendered effective in manner as just described.

Since the governor valve device I9I is in its closed position with shaft I00 yet to turn because the friction clutches I06, I01 are still disengaged, upon venting of the pipe 231 to atmosphere as above, fluid under pressure will flow by way of pipe 238 and choke 238', the purpose of which will be described hereinafter, from the control chamber 35 in the relay valve device I86. The relay valve device I86 then responds to connect the pipe 239 to atmosphere by way of the pipe 243 and the choke 244, through establishment of communication I95. With the pipe 239 thus vented to atmosphere, the control chamber of the relay valve device I12 is thereby so vented by way of pipe I88 and double check. valve I89 both inlets of which are now so vented. One inlet of the double check valve I89 is also vented by pipe 239 but due to pressurization of pipe I18 the opposite inlet of said double check valve I89 remains charged with fluid under pressure as therefore does the pipe I89 and the control chamber in the relay valve device I11. The chambers 36 in the relay valve devices I14, I19 are also now vented to atmosphere by way of said pipe 239.

Venting of fluid under pressure from the control chamber in the relay valve device I12 renders said device efiective to disconnect the pipe I13 from the pipe HI and to connect said pipe I13 to atmosphere by way of pipe I95 thus preventing the possibility of supply of fluid under pressure to pipe I13 from the control valve device I10 at this time. The relay valve device I11 with its control chamber 35 charged remains positioned connecting pipe I18 to the pressurized pipe I16. Since the control chamber 35 in the relay valve device I14 is now void of fluid under pressure, when fluid under pressure is vented from the chamber 36 therein, said device does not react to such venting and remains positioned connecting pipe I15 to pipe I13 and thereby to atmosphere. However, in the relay valve device I19, its control chamber 35 is charged with fluid under pressure at the time that fluid under pressure is vented from its chamber 36 so that said device I19 is thereby rendered responsive to establish communication I96 to connect pipe I30 to the supply pipe 24 and thereby maintain the chamber I59 in the actuator I55 charged with fluid under pressure and the high speed jaw clutch I38 engaged.

If for any reason it is now desired to eifect dis.- engagement of the high speed jaw clutch, the handle I3I on the jaw clutch control valve device I10 may be moved back to its Neutral position, thus effecting venting of fluid under pressure from the pipe I16 along with the pipe I1I which re mains so vented. The pipe I10 is now vented to atmosphere by way of the communication 2953 the relay valve device I11 and the pipe I16, so that fluid under pressure is thus vented from the control chamber in the relay valve device to again establish communication between the supply pipe 24 and the pipe 231. Fluid under pressure is then supplied to pipe 231 to again effect application of the brake on shaft I95 and to condition the relay valve device I36 to disconnect the pipe I35 from the supply pipe 24 and to con" nect said pipe I35 to atmosphere for rendering the control valve device I30 ineffective. At the same time, since the governor valve device I9! is still in its closed position due to the friction clutches I06, I01 not having been engaged, fluid under pressure from pipe 231 in flowing from pipe 231 through choke 238 will effect pressurization of pipe 230 and thereby the control chamber in the relay valve device I86 which then responds to connect the pipe 239 to the now charged pipe 231. Fluid under pressure from pipe 23? then flows into the pipe 239, thence to the control chamber 35 in each of the relay valve devices I12, I11 by way of the respective double check valve devices I88, I and the respective pipes I68, I89, and into the chamber 36 in each of the relay valve devices I14, I19.

The relay valve device I 12 reacts to pressurization of its control chamber 35 to disconnect the pipe I13 from the pipe I95 open directly to atmosphere and to connect said pipe I13 to the pipe "I now open to atmosphere, while the relay valve device I11 responds to pressurization of its corresponding control chamber to connect the pipe I18 to the pipe I16 which is also now open to atmosphere. The relay valve device I 14, since its control chamber 35 is void of fluid under pressure when its chamber 36 is pressurized, will remain in its previous position connecting pipe I 15 to the pipe I 13 and to atmosphere by way of relay valve device I12, pipe I1! and the control valve device I 10. The relay valve device I19, however, will respond upon pressurization of its chamber 36 to disconnect the pipe I80 from the supply pipe 24 and to connect said pipe I 80 to the pipe I18, thereby venting said pipe I80 to atmosphere by Way of the pipe I18, relay valve device I11, pipe I16 and the control valve device I10. Fluid under pressure in the chamber I59 in actuator I55, and the control chamber 35 in the relay valve device I19 is thus released to atmosphere by way of the pipe I89. The actuator I55 then assumes its neutral position, in response to release offluid under pressure from its chamber I59, thereby effecting disengagement of the high speed jaw clutch I38 through actuation of lever I64, as will be obvious from previous description of operation of said actuator.

Assume now that the handle I 3| of the jaw clutch control valve device I is in its Low speed position in which the parts of the apparatus have assumed positions in the manner as previously described in regard to moving the operators handle I3I in control valve device I10 from its Neutral position to its "Low speed position. The pipe I1I is pressurized and the pipe I16 is vented to atmosphere by control valve device I 10. The control chamber 35 in the relay valve device I12 is charged with fluid under pres sure from the pipe I13 which is connected to the pressurized pipe I1I by Way of communication I 95 in said relay valve device. The control chamber 35 in the relay valve device I85 is pressurized from pipe I13 by way of double check valve I81 so that said relay valve device I35 is connecting the pipe 231 to atmosphere by way of pipe 24! and choke 242 thereby venting the chamber 202 in brake cylinder device I99, and the control chamber 35 in the relay valve device I 36 to atmosphere. The brake on shaft I05 is therefore in its released position and the relay valve device I36 is positioned connecting pipe 35 to supply pipe 24 by way of communication I95 and choke 236 so that the control valve device 30 is effective. The shaft M35 is yet to turn, so that the governor valve device I9! is in its closed position. The pipe 233 and thereby the control chamber 35 in the relay valve device 186 is vented to atmos phere by way of choke 238' and the pipe 231. The relay valve device I35 is therefore in its position connecting pipe 239 to atmosphere by way of the pipe 243 and choke 244. By way of pipe/239, the common inlets to both of the double check valves I83 and I89 are vented to atmosphere as are the respective chambers 36 in the relay valve devices I 14, I19. The pipe I18 is vented to atmosphere by way of the communication I95 in relay valve device I11, the control chamber .of which is open to atmosphere by way of the pipe I89 and one or the other of the opposite inlets of double check valve I89 both of which inlets are vented to atmosphere. The relay valve device [74,

its position connecting pipe I 15 to the supply pipe 24 by way of communication I95, since its control chamber 35 is pressurized from pipe I15 and its chamber 36 is vented to atmosphere by way of pipe 239. The chamber I58 in actuator I is pressurized from pipe i15 now connected to the supply pipe 24. The relay valve device I19 is positioned connecting the pipe I30, and thereby the chamber I59 in actuator I55 and the control chamber of said relay valve device, to the pipe I18 and thus to atmosphere. With its chamber I58 pressurized and its chamber I 59 vented, the jaw clutch actuator I55 is positioned for engagement of the low speed jaw clutch I 31.

Now with the control apparatus positioned and conditioned as above, assume that the operators handle I3I of the jaw clutch control valve device I10 is moved directly from its Low speed position to its High speed position, without stopping in Neutral position, to effect disengagement of the low speed jaw clutch I31 and engagement of the high speed jaw clutch I38.

In High speed position of handle I3I, the control valve device I10 supplies fluid under pressure to the previously vented pipe I16 and vents the previously charged pipe l1I to atmosphere. At this time, pressure of fluid supplied to the pipe I16 is blanked off by the relay valve device I11 which is positioned, as aforementioned, to connect pipe I18 through pipe 240 to atmosphere so that fluid under pressure in pipe I16 cannot yet reach said pipe I18. However, at the time that pipe IN is vented, same is connected to the pipe I 13 so that fluid under pressure from the control chamber 35 in relay valve device I will release by way of pipe 242, double check valve I81 and said pipe I13, as Will fluid under pressure in the corresponding control chamber in the relay valve device H2, by way of pipe I88 and double check valve I39. At this time fluid under pressure in pipe I15 is prevented from releasing by way of pipe I13 by the relay valve device I14 which is positioned as aforedescribed to connect said pipe I15 to the supply pipe 24.

With release of fluid under pressure from its control chamber, the relay valve device I12 will respond to connect the pipe I15 to pipe I to atmosphere, and with release of fluid under pressure from the corresponding control chamber in the relay valve device I35 said device assumes its position to disconnect pipe 231 from pipe 2M to atmosphere and to connect said pipe 231 to the supply pipe 24 by establishment of communication I95. Fluid under pressure from supply pipe 24 then flows into pipe 231 to the chamber 202 in brake cylinder device I99 to apply the brake on shaft I 35 and to the control chamber in relay valve device I36 to vent pipe I35 to atmosphere and thereby render the friction clutch control valve device I38 ineffective. At the same time, with the governor valve device I9I in its closed position, pipe 238 and thereby control chamber 35 in the relay valve device I36 becomes pressurized from pipe 231 by way of choke 238. The relay valve device I 85 then assumes its position connecting the pressurized pipe 231 to the pipe 239 by establishment of the communication I96. Fluid under pressure from pipe 231 then flows into pipe 239 to the control chamber in each of the relay valve devices I12 and I11 by way of the respective double check valves I38, I89 and into the respective chambers 35 in the relay valve devices I14, I19.

In response to supply of fluid under pressure 'to their respective control chambers, the relay '19 valve device I12 will connect pipe I13 to the vented pipe HI, and the relay valve device I11 will connect the pipe I18 to the pressurized pipe I16. Fluid under pressure in pipe I18 then flows to the control chamber in the relay valve device E85 and to the chamber I59 in actuator I55 by way of pipe I80 and communication I95 in relay valve device I19. With both chambers I58, I59 in actuator I55 charged with fluid under pressure said actuator will tend to assume its neutral position disengaging clutch I31. At the same time with its chamber 36 pressurized, the relay valve device I14 assumes its position connecting pipe I15 to the pipe I13 to atmosphere by way of the communication I96 in relay valve device I12, the pipe HI and control valve device I10. Fluid under pressure in the chamber I58 in actuator IE is thus released by way of pipe I15, communication I95 in relay valve device I14, and pipe I13, allowing pressure of fluid in chamber I59 of said actuator to effect engagement of the high speed jaw clutch I38. The pressure of fluid in the chamber 36 in relay valve device I19 nullifies the effect of pressure of fluid in its control chamber 3'5, so that said device at this time remains positioned connecting pipe I80 to pipe I18.

At the time that pipe I18 is pressurized, fluid under pressure supplied to the control chamber of the relay valve device 85 will render said device responsive to establish its communication I96 again and thereby revent pipe 231 to atmosphere by way of the pipe MI and the choke 242. Choke 242 acts to restrict release of fluid under pressure from pipe 231 to allow sufficient time for engagement of the high speed jaw clutch I38 before the brake on shaft I05 is released and the control valve device I30 is rendered effective through such release in manner aforedescribed. Fluid under pressure in pipe 238, hence control chamber 35 in the relay valve device I86, releases into the pipe 231 by way of choke 238'. The relay valve device I86 then responds to such release of fluid under pressure from its control chamber to connect the pipe 239 to atmosphere by way of pipe 243 and choke 244 through establishment of communication I95. Fluid under pressure is thus released by way of pipe 239, from the respective inlets of double check valves I88, I89 having a connection with said pipe common to both, and from the respective chambers 36 in the relay valve devices I14, I19.

With the opposite inlet of double check valve I89 pressurized from pipe I18, the pipe I89 and the control chamber in the relay valve device I11 remain pressurized when pipe 239 is vented to atmosphere and therefore the pipe I18 remains connected to the pipe I16 by way of the communication I96 in said relay valve device. Since, however, at the time that pipe 239 is vented to atmosphere, the pipe I13 is also so vented, both inlets to double check valve I88 are then vented and fluid under pressure in the control chamber of the relay valve device I12 releases to atmosphere by way of the pipe I88 and said double check valve. The relay valve device I12 then assumes its position disestablishing communication 96 and establishing communication I95 and thereby disconnects pipe [H from pipe I13 and connects the latter pipe to pipe I95 to atmosphere.

' With the relay valve device I14 in its position establishing communication I95 between pipes I15 and I13 to effect release of fluid under pressure from said pipe I15, when chamber 38 is vented to atmosphere by way of pipe 23 9, if pipe I15 is then void of fluid under pressure said relay valve will remain in such position since its control chamber connected to said pipe I15 will not be charged. If, on the other hand, at the time that fluid under pressure is released from its chamber 36 the pipe I15 was not yet void of fluid under pressure, there is a possibility that resultant pressure of fluid in its control chamber would effect positioning of the relay valve device I14 to reconnect said pipe I15 to supply pipe 24, as is not desired. The choke 244, however, prevents rapid release of fluid under pressure from the pipe 239, thereby chamber 36 in the relay valve device I19, so that the relatively great volume of fluid under pressure in chamber I58 in actuator I 55 has ample time to release by way of pipe I15 and communication I in said relay valve device I14 before complete reduction in pressure of fluid in its chamber 36, so that said device then remains positioned connecting pipe I15 to pipe I13 to atmosphere by way of communication I95 in relay valve device I12 and the pipe I95.

The high speed jaw clutch is now engaged, with handle I3I on the jaw clutch control valve device I10 in its High speed position after having been moved directly thereto from its Low speed position. The friction clutch control valve device I30 has remained in a neutral position, with both friction clutches I06, I01 disengaged.

With both of the friction clutches disengaged and the transmission yet to be operated, in manner similar to the above-described operation of the control apparatus in effecting disengagement of the low speed jaw clutch I31 and engagement of the high speed jaw clutch I38 by movement of handle I3I on the control valve device I10 directly from its Low speed position to its High speed position, it will be appreciated that conversely the high speed jaw clutch I38 may be disengaged and the low speed jaw clutch I31 reengaged by movement of said handle I3I on said control valve device I10 from its High speed position directly to its "Low speed position.

According to a, feature of the invention, the friction clutches I06, I01, may not be engaged until one or the other of the jaw clutches I31, I 38 is first engaged. When the handle I3I on the jaw clutch control valve device I10 is in its Neutral position, and therefore both jaw clutches I31, I38 are disengaged, as will be appreciated from preceding description of operation, the pipe I35 for supplying fluid under pressure to the friction clutch control valve device I 30 is vented to atmosphere thereby rendering said device I30 ineffective and preventing engagement of either the friction clutches I06, I01. When handle I3I on the jaw clutch control valve device is moved to either Low speed or High speed position and either the low speed jaw clutch I31 or the high speed jaw clutch I38 is therefore engaged, the pipe I35 for supplying fluid under pressure to the friction clutch control valve device I30 is connected by way of the relay valve device I36 and choke 236 to the supply pipe 24 thereby rendering said friction clutch control valve device operable to effect supply of fluid under pressure to one or the other of pipes I32, I33 for causing engagement of one or the other of friction clutches I06, I01.

Suppose now that handle I3I of the jaw clutch control valve device I10 is in Low speed position pressurizing pipe "I and venting pipe I16 to atmosphere, with the low speed jaw clutch I31 in engagement and parts of the control apparatus' in positions assumed after effecting such engagement as previously described and in which:

The relay valve device I12 is in its position connecting the pipe I13 to the pressurized pipe I11 and held in such position by pressure of fluid in said pipe I13 by way of the double check valve I88 and the pipe I88;

The relay valve device I85 is in its positionconnecting the pipe 231 to atmosphere by way of the pipe MI and the choke 242 and is also held in such position by pressure of fluid from the pipe I13 by way of the pipe 242' and the double check valve I81;

The brake cylinder device I90 is in its release position with its chamber 202 vented to atmosphere by way of the pipe 231;

The relay valve device I36 is in its position connecting the pipe I35 to the supply pipe 24 by way of choke 236 since its control chamber is vented to atmosphere also by way of pipe 231;

The governor valve device I9I is in its closed position, in which it is shown in the drawing, closing off chamber 208, hence pipe 238 from ports 2I0 to atmosphere;

The relay valve device I86 is in its position connecting the pipe 239 to atmosphere by way of pipe 243 and the choke 244 and is in such position by virtue of the fact that its control chamber is vented to atmosphere by way of the pipe 238, the choke 238 and the pipe 231;

The relay valve device I14 is in its position connecting the pipe I15 to the supply pipe 24 and is held in such position by virtue of the fact that its control chamber 35 is pressurized from the supply pipe 24 via I15 while its chamber 36 is vented to atmosphere by way of the pipe 239; B

And the relay valve device I19 is in its position connecting the pipe I80 to the pipe I18, hence to atmosphere, and is in such position by virtue of the fact that its control chamber 35 is vented to atmosphere by way of the pipe I80. The chamber 36 in the relay valve device I13 is also vented to atmosphere by way of pipe 239.

Assume now that- With the handle I3I of the jaw clutch control valve device in Low speed position, with the low speed jaw clutch therefore engaged and with parts of the apparatus positioned as above defined, the handle I3I of the friction clutch control valve device I30 is moved from its Neutral position to either its "Low speed position or to its High speed position for connecting the now pressurized pipe I35 to either the pipe I32 or I33 for effecting engagement of either the friction clutch I06 or I01 in manner as previously described.

With one or the other of the friction clutches I06, I01 engaged, shaft I will be driven by the input shaft 1I through either chain I2I or chain I24, and said shaft I05 in turn will drive sprocket wheels I42, I45 through chains I43, I46. Sprocket wheel I42 will be operatively connected t the output shaft I00 through jaw clutch element I40 due to engagement of the low speed jaw clutch I31, while sprocket wheel I45 will rotate freely relative to said shaft I00. Shaft I00, therefore, is caused to turn to drive whatever devices are operably connected thereto. Upon initial turning movement of shaft I00, the speed governor device I92, acting through rack element 2I-1, gear 2I6 and cam 2| 4, as previously described, will cause the valve 209 in governor valve device I9I to open, thus venting the pipe 238 to atmosphere by way of chamber 208 and ports 2I0 in said valve device, without affecting the status of the pipe 231 at this time since same is already vented by way of relay valve device I85.

With the output shaft I00 thus being driven at some speed proportional to the speed of the input shaft 1 I, assume that it is desired to change the ratio between speed of the input shaft H and speed of the output shaft I00. The handle I 3I of the friction clutch control valve device I30 may be shifted from one position to another to disengage one friction clutch and engage the other to obtain a change in a certain speed ratio, since the friction clutches may be engaged or disengaged at any speed.

If, however, it is found desirable to effect an increase in ratio between speed of output shaft I00 to input shaft II through a, change in jaw clutches I31, I38, handle I3I of the jaw clutch control valve device I10 may be moved from its Low speed position through Neutral to its High speed position while one or the other of the friction clutches I08, I01 remain engaged. During such movement of handle I3I, valve device I 10 will respond first to vent pipe I1I to atmosphere and then to effect supply of fluid under pressure to the pipe I16.

At this time, due to position of the relay valve device I11, the now pressurized pipe I16 is blanked ofi" from the pipe I10 which remains open to atmosphere by Way of communication I 05 in said relay valve device and the pipe 240. Pipe I13, however, being connected to pipe I' l through communication I95 in the relay valve device I12 at the time said pipe I1I is vented to atmosphere will allow for release of fluid under pressure from the control chamber 35 in said relay valve device I12 by way of pipe I88 and double check valve I68 and from the corresponding control chamber in the relay valve device I85, it being realized that with venting of pipe I13 to atmosphere at this time both inlets of both of the double check valves I38, I81 will be open to atmosphere since pipes 233 and I18 are so vented. Also at the time that p p I13 is vented to atmosphere through pipe I1I, the relay valve device I16 is in its position disconnecting pipe I15 from pipe I13 and connecting said pipe I15 to the supply pipe 20, so that the chamber I58 in actuator I55 and the control chamber in said relay valve device yet remains pressurized. The relay'valve device I19 remains positioned connecting pipe I to the vented pipe I18 since the status of its chambers 35, 36 remain unchanged. The chamber I53 in actuator I 55 remains vented to atmosphere by Way of the pipe I 80, and with chamber I 58 pressurized said actuator maintains its previous position holding the low speed jaw clutch I31 in engagement.

With fluid under pressure vented from its control chamber 35, the relay valve device I12 will assume its position connecting pipe I13 to the pipe I95 and thereby to atmosphere as before but at the same time disconnecting said pipe I13 from the vented pipe I1I'.

In response to venting of fluid under pressure from its control chamber, the relay valve device I85 will assume its position for disconnecting the pipe 231 from the pipe 24I to atmosphere and connecting said pipe 231 to the supply pipe 24 for effecting supply of fluid under pressure to said pipe 231 and thereby to the chamber 202 in brake cylinder device I90 and. to the control chamber in the relay valve device I35 for simultaneously effecting application of the brake on shaft I05 and venting the pipe I35 to atmosphere to release fluid under pressure from whichever of the pipes I32, I33 may be charged and thereby releasing whichever of the friction clutches I05, I01 Was engaged at the time, as will be understood from previous description. The driving connection between the input shaft 1I and the intermediate shaft I05 is terminated with the automatic disengagement of the previously engaged friction clutch I06 or I01 to allow application of the brake on shaft I05 to slow down and substantially stop rotation of the remaining connected parts of the transmission including the shaft I00. handle I3I on the friction clutch control valve device I30 may remain in either High speed or Low speed position connecting one or the other of pipes 132, or I33 to the now vented pip I35.

At the time that fluid under pressure is supplied to the pipe 231, the shaft I will be turn ing and will continue to turn after application of the brake on shaft I until such application slows it down to a stop. The governor I92 will maintain the valve 209 in governor valve device I9I open until substantially the time that shaft I00 ceases rotation. The pipe 239, and therefore the control chamber in relay valve device I80, will remain open to atmosphere by way of the relatively large ports 2I0 in the governor device I9I until the shaft I00 substantially stops. The choke 233 will allow passage of a limited volume of fluid under pressure from pipe 231 into pipe 230 which will be too limited to cause pressurization of pipe 238 when valve 209 is Open. Choke 230' also prevents excessive leakage of fluid under pressure from the pipe 231 to at mosphere via pipe 230 and the unseated valve 209. As long as valve 209 is open, therefore, the relay valve device I80 will remain in its position connecting the pipe 239 to the pipe 243 to atmosphere via choke 244 thus maintaining the relay valve devices I14 and I11 in their positions preventing release of fluid under pressure from chamber I58 and supply of fluid under pressure to chamber I59, respectively, in the jaw clutch actuator I55 which therefore remains in its position holding the low speed jaw clutch I31 in engagement.

When the brake on shaft I05 effects stoppin of shaft I00, or substantial stopping thereof, and the valve 209 in the governor valve device I3I is therefore closed by action of the speed governor I92, fluid under pressure flowing through choke 238' from pipe 231 into pipe 230 and the control chamber 35 in the relay valve device I86 will effect pressurization thereof and cause said relay valve device to assume its position connecting pipe 239 to the pressurized pipe 231 so that fluid under pressure will then flow from said pipe 231 into said pipe 230.

Fluid under pressure thus supplied to the pipe 230 will then flow to the respective control chambers in both the relay valve devices I12, I11 by way of the respective double check valves I38, I89 and pipes I38, I89 and to the respective chambers in the relay valve devices I14, I19.

The relay valve devices I12, I11 respond upon The supply of fluid under pressure to their respective control chambers to disestablish their respective communication I95 and to establish their communication I96, connecting pipe I13 t0 the vented pipe HI and connecting the pipe I18 to the pressurized pipe I16, respectively, to allow fluid under pressure to flow from said pip I16 into said pipe I18.

At the same time, fluid under pressure supplied to the chamber 36 in the relay valve device I14 will nullify the effect of pressure of fluid in its control chamber 35 and render said device responsive to disconnect the pipe I15 from the supply pipe 24 and to connect said p p I15 to the pipe I13. Fluid under pressure in the chamber I58 in the jaw clutch actuator I and in the control chamber in relay valve device I14 will then release to atmosphere by way of communication I95 in said device I14, p pe I communication I96 in the relay valve device I12, pipe Ill and the control valve device I10. After completion of such release of fluid under pressure from its control chamber the relay valve device I14 will remain in the same position con necting pipe I15 to pipe I13, as will be obvious.

Simultaneous supply of fluid under pressure to the chamber 33 in the relay valve device I19 will act to maintain said device in its position establishing its communication I95 to continue supply of fluid under pressure from the pipe I18 to pipe I00 and thence to the chamber I59 in the jaw clutch actuator I55 and into the control chamber of said relay valve device.

The jaw clutch actuator I55 will respond upon release of fluid under pressure from its chamber I58 and supply of fiuicl'under pressure to its chamber I59 to move to and through its neutral position, disengaging the low speed jaw clutch I31, to its opposite extreme position for engaging the high speed jaw clutch I38, as will be understood from previous description.

At the time that fluid under pressure was supplied to the pipe I18,thence to the pipe I via the relay valve device I19 as above described such fluid under pressure in pipe I18 will also flow into the control chamber of the relay valve device I85, causing said device I to effect venting of fluid under pressure from the pipe 231 by way of pipe 24I and choke 242 for releasing the brake on shaft I05 and for effecting connection through relay valve device I36 between the supply pipe 24 and pipe I35 to the control valve de vice I30 and thereby to whichever one of pipes I32, I33 is connected to said pipe I35 as determined by position of handle I3I of said device I30 to cause automatic reengagement of the previously engaged friction clutch I05, or I01. The choke 242 restricts release of fluid under pressure from the pipe 231 and thereby allows sufficient time for operation of actuator I55 to disengage clutch I31 and engage clutch I38 as above described before the friction clutch I05 or I01 is automatically reengaged and the brake on shaft I05 released. The choke 233 in the branch of the supply pipe 24 connected to the relay valve device I36 acts to restrict flow of fluid under pressure from said supply pipe through said relay valve device, pipe I35, control valve device 30, and one or the other of pipes I32, I33 to one or the other of clutch actuators I03, I09 to prevent suddenshock engagement of the friction clutch I06 or I01.

With automatic reengagement of one or the other of the friction clutches I06, I01, and engagement of the high speed jaw clutch I38, the

valve device I'9 I, thus opening the pipe 2'38 to atmosphere by Way of the ports 2 I said de vice I9I. Fluid under pressure the control chamber 35 of the relay valve device I86 will then flow to atmosphere by way of pipe 238, the unseated valve 209 and ports 2 I0 valve device: I 9 I if such has not already occurred by way of choke- 23'8 and the vented pipe 231.

Upon venting of fl uid under pressure from the control chamber in the relay valve device I83, same will respond to connect the pipe 239 again toatmosphere by way of pipe 243 and choke 244 thus releasing fluid under pressure from the chamber 35 i'neach of the relay valve devices I14, I19 and from the control chamber inthe relay valve device I12, since both inlets to double check valve i88 are then vented to atmosphere. The control chamber in the rel'ayvalve device I11 will remain pressurized by way of pipe I89", double check valve I80 and the pipe ITB so that position of said relay valve device I11 will remain unchanged connecting said pipe I18 to the pressurized pipe I16.

Upon release of fluid under pressure from its control chamber, the relay, valve device I12 will respond to disconnect pipe I13 from the vented pipe H fand connect said pipe I13? directly to atmosphere by way of pipe I95" through establishment of communication I95.

Upon release of fluid under pressure from itschamber 36, the relay-valve device I14 will remain in its position establishing communication I 95 and thereby connecting pipe l'l-5t0 the vented pipe I13 as before since the control chamber 35 26 vice [1121 which is its position connecting pipe I13 to atmosphere by way of pipe I95.

Venting of thepipe I316 to atmosphere, however, since the relay valve device. I11 is in its. position connecting thepipe II B: to the pipe I15 at. the time said pipe I '16 is vented to atmosphere, will effect release of fluid under pressure from the control chamber in said. relay valve device I'It by way of pipe I89? and: double: check: valve 2 I 89: due to the fact that pipe 239 is also so vented and front the control chamber in the relay valve device t85 by way off the pipe 242" and double valve: 128m, due to the fact that both inlets to said double check. valve I81 are thenvented to atmosphere via pipes I13, I18. The

now vented? ipe I131 is prevented fromv releasing fluid under pressure from the: pipe: I 80 at: this time: by the relay val ve device I19 in its position establishing communication I85 and. connecting said pipe Ildfl to the supply pipe 21. When fluid under pressure is vented as above mentioned from the control chamber in relay valve device- I1'1', said. device will: assume its position disconmeeting: the pipe I18 from the vented pipe I16 in said relay valve device is open to atmosphere 0 with said pipe I15.

Upon release of fluid under pressure from the chamber 36 in the relay valve device I 19, the pressureof fiiuicl from pipe I80 in its control chamber 35- will become effective to caused-isestablishment of its communication I95 and establishment of its communication I96 to thereby disconnect pipe I80 from pipe "Band to connect said pipe [30 to the supply pipe 24 to maintain pressure of fluid in the chamber I59 in the jaw clutch actuator I for holding the high speed jaw clutch I 38 in engagement.

Now with the shaft I00 being driven with the high speed jaw clutch I38 engaged, assume that it is desired to effect disengagement thereof and engagement of the low speed jaw clutch I31. The operator will then move handle I3I on the jaw clutch control valve device I 10 from its High speed position to its Low speed position, thereby venting the formerly pressurized pipe I16 to atmosphere and pressurizing the formerly vented pipe I.1I1 Again assume that the handle I'3I on the; friction clutch control valve device I30 remains in either its High speed or its Low speed position connecting one or the other of pipes I32, I33 to the pipe I35 for effecting engagement of one or the other of the friction clutches I 06, I 01, as willbe understood from previous description.

At this time fluid under pressure supplied to pipe I1I to effect its pressurization is prevented from reaching the pipe I13 by the relay valve de-- and. connecting: said pipe: I 1 8- directly to atmosphone: by: way of the pipe: 240- through disestablishment of communication we and establishment of communication, N35.

When fluid under pressure is vented as abovementioned from the controI chamber inthe relay valve device I185, said device: will assume its position disconnecting 2-3 1 irom pipe 2 4! to at.- mosphere and connecting said pipe 2 31 tothe fluid pressure supplypipe-Zt through disestablishmerit of communication I 96 and establishment of communication I 95, whereupon fluid under ressure from said pipe M will; into said pipe 231 tothe pressure chamber 20?: in brake cylinder device to apply a braking: force on: shaft Hi5 and to the control chamber of the relay valve device I 36 for causing the pipe I35- to be vented to atmosphere for effecting disengagement of whichever of the friction clutches I06, I01 was in engagement; in manner'similar to that previously described.-

At the time that fluid under pressure is thus supplied to the pipe 231, the shaft I100 still will be turning so; that: valve 200 in the governor? valve device I290 wiili be open and preventing pressurization of the pipe 238 the restricted flow'of fluid under: pressure frompipe 23 "ii through choke: 23 8" into: said pipe 238; The relay valve: device-I03 at-this time therefore. will? remain in itsn position connecting pipe 25$ toatmosphere viapipe-243 and thereby preventinga change'in positionof the relay valve device I 12 to admit fluid under pressure from the charged pipe I11 to the pipe I13 and preventing a changein position of the relay valve device I19 to effect release of fluid underpressure from the pipe I80 by way of the pipe I18.

When due to automatic disengagement of the previously applied friction clutch r0601" I01 and application of abrakingforce onthe shaft I65, the shaft I-00'- is brought to a stop; the governor I 92 will cause th valve 209 in governor valve device I 9I to close, thus allowing'fluid under pressure flowing into pipe 238 through choke 238 to build up and effect a change in position of the relay valve device F86 to connect pipe 239' to the pressurized pipe-231. Fluid under pressure fromrespectively, and to the chamber 36 in each of the relay valve devices I14, I19.

The relay valve device I11 will respond upon supply of fluid under pressure to its control chamber to disconnect the pipe I18 from the pipe 240 to atmosphere and to connect said pipe I18 by way of communication I96 to the pipe I16 and thereby to atmosphere.

Since its control chamber 35 is vented to atmosphere with pipe I15 at the time that its chamber 36 is thus supplied with fluid under pressure from the now pressurized pipe 239, the relay valve device I14 will remain positioned as before, connecting pipe I15 to the pipe I13 by way of communication I95.

Since, in relay valve device I19, the control chamber 35 is charged with fluid under pressure from pipe I80 at the time that fluid under pressure is supplied to the chamber 35 from pipe 239, said relay valve device will efiect connection between said pipe I80 and the pipe I18, whereby fluid under pressure from the chamber I59 in actuator I55 and from saidcontrol chamber will flow by way of communication I05, pipe I18, communication I96 in the relay valve device 111, pipe I16, and control valve device I10 to atmosphere.

At the same time, in response to supply of fluid under pressure from pipe 239 to the control chamber in the relay valve device I12, said relay valve device will assume its position connecting the pressurized pipe I1I to the pipe I13, whereupon fluid under pressure will flow from said pipe I1 I, through the communication I96 in said relay valve device I12 into the pipe I13, thence to the control chamber of the relay valve I85 by way of double check valve I81 and to the chamber I58 in the actuator I55 by way of the communication I95 in the relay valve device I14 and pipe I15. Fluid under pressure thus supplied to the pipe I15 will also flow into the control chamber in the relay valve device I14.

With fluid under pressure thus supplied to its chamber I58 and released from its chamber I59, the actuator I55 will effect disengagement of the high speed jaw clutch I33 and ngagement of the low speed jaw clutch I31.

At the time that such clutch shifting is thus being effected, the relay valve device I85 will respond to supply of fluid under pressure from pipe I18 to its control chamber to connect-thepipe 231 to the pipe 24I, whereupon fluid under pressure will release from the chamber 202 in brake cylinder device I90 and from the control chamber in relay valve device I36 to atmosphere by way of said pipe 231, communication I96 in said relay valve device I85, said pipe MI and the choke 242.

Release of fluid under pressure from chamber 202 in brake cylinder device I90 will release the brake on shaft I while release of fluid under pressure from the control chamber in the relay valve device I36 will cause said device to effect connection between the pipe I35 and the supply pipe 24 to automatically effect engagement of the .previously engaged friction clutch I09 or I01, to

drive the transmission as will be appreciated from previous description.

Choke 242 so restricts release of fluid under pressure from pipe 231 as to provide sufficient time for shifting of the jaw clutch I31 or I38 before the brake on shaft I05 is released and the friction clutch I06 or I01 reengaged.

At the time that the pipe 231 is vented to atmosphere the pipe 239 is connected thereto through the relay valve device I86 which willremain in its position connecting pipes 231, 239

28 until fluid under pressure is released from its control chamber by way of pipe 238, choke 238 and said pipe 231 or by way of said pipe 238 and the governor valve device I9I which is caused to assume its open position upon rotation of the output, shaft I00 when the friction clutch I06, or I01 is automatically reengaged as above. Upon release of fluid under pressure from its. control.

chamber, the relay valve device I86 will disconnect the pipe 239 from the now vented pipe 231 and connect said pipe 239 to atmosphere by way of communication I95, pipe 243 and chok 244.

Upon venting of the pipe 239 to atmosphere both by way of pipe 231 and choke 242 and subsequently by Way of pipe 243 and choke 244, fluid under pressure is released from the control chamber in the relay valve device I11 by way of double check valve I89 since both of its inlets arenow vented to atmosphere via pipes 239 and I18, respectively, and from the chamber 38 in each of the. relay valve-devices I14, I19. The control chamber in the relay valve device I12, will remain pressurized by way of double check valve I88 and pipe. I13.

Venting of fluid under pressure from the control chamber in the relay valve device I11 by way of pipe 239 will cause said device to disconnect the pipe I18 from the vented pipe I16 and to connect said pipe I18 to atmosphere via communication I95 and pipe 240.

Since at the time that fluid under pressure is vented via pipe 239 from its chamber 36 its control chamber is void of fluid under pressure with pipe I80, the relay valve device I19 will remain in its position connecting said pipe I to the pipe I18 and hence to atmosphere.

Conversely, at the time that the chamber 36 in the relay valve device I14 is vented to atmosphere by way of pipe 239 the control chamber 35 of said device is charged with fluid under pressure with pipe I15, so that said device will assume its position for disconnecting said pipe I15 from .the pressurized pipe I13 and connecting said pipe I15 to the supply pipe 24 for maintaining the actuator in position for holding the low speed jaw clutch I31 engaged.

Now assume that with the output shaft I00 being driven through one or the other of the friction clutches I66 or I01 and the low speed jaw clutch I31, and with the parts of the apparatus in the positions assumed as above described, that it is desired to effect disengagement of said low speed jaw clutch. The handle I3I on the jaw clutch control valve device I10 will then be .moved from its Low speed position to its Neutral position thereby causing pipe I to be vented to atmosphere along with the pipe I16.

With venting of the pipe I1I to atmosphere, the pipe I13 is also vented by way of the relay valve communication I06 in the relay valve device I12 and said pipe I1I. Fluid under pressure is thus released via pipe I13 from the control chamber in the relay valve device I12 by way of double check valve I88 since pipe 239 is at this time also so vented, and from the control chamber in the relay valve device I by way of the double check valve I81, since pipe I18 is at this time also so vented.

The relay valve device I14 remain in its position disconnecting pipe I15 from pipe I13 at this time so that fluid under pressure in chamber I58 in actuator I55 will not yet release and the low speed jaw clutch I31 remains in engagement.

The relay valve device I12 responds to venting of fluid under pressure from its control chamber to disconnect pipe I13 from the now vented pipe Ill and to connect said pipe I13 to the pipe I95 to atmosphere.

The relay valve device I85 respond to venting of fluid under pressure from its control chamber by effecting connection between the pipe 231 and the supply pipe 24 whereupon fluid under pressure from said pipe 2 will flow via communication 95 in said relay valve device into said pipe 231 to the chamber 262 in the brake cylinder device I36 and to the control member in the relay valve device I86.

At this time shaft I 69 will still be turning so that the governor valve device I9I will be in its open position preventing pressurization of pipe 238, hence the control chamber in the relay valve device I 85, from the pipe 231 via choke 238". The relay valve device I86 at this time remains positioned to vent pipe 239 to atmosphere via pipe 243.

Supply of fluid under pressure to chamber 202 in brake cylinder device I90 will apply the brake on shaft I95, while supply of fluid under pressure to the control chamber in relay valve device I36 causes venting of pipe I35, hence whichever of pipes I32, I33 may be connected thereto, to atmosphere to release whichever of the friction clutches I96, I01 is engaged.

With disengagement of the engaged friction clutch I96 or Hi1 and application of the brake on said shaft I535 and through the low speed jaw clutch I 31 the shaft I 95 Will be brought to a stop, whereupon the governor I92 will cause the governor valve device I St to assume its closed position, allowing fluid under pressure from pipe 23? flowing through choke 238' to pressurize the pipe 238 and control chamber in the relay valve device I36.

In response to pressurization of its control chamber, the relay valve device I86 will connect the pipe 239 to the pressurized pipe 231, whereupon fiuid under pressure will flow from said pipe 231 through communication I 96 in said relay valve device into said pipe 239 to the control chambers in each of the relay valve device I12, I11 by way of double check valves I98, I89, respectively, and into the chamber 36 in each of the relay valve devices I14, I19.

Both relay valve devices I12, I11 will respond upon supply of fluid under pressure to their control chamber to effect connection between the previously vented pipes I13, I18 and the now vented pipes I1I, I16 respectively, through establishment of their respective communication I96.

The relay valve device I19 will remain in its position connecting pipe I89 to the vented pipe I18 after fluid under pressure is supplied by way of pipe 239 to its chamber 36 since its control chamber is void or" fluid under pressure with said pipe I89. The chamber I59 in the actuator I55 will therefore remain vented to atmosphere by way of pipe I 89., communication I95 in relay valve device I19, pipe I13, communication I96 in relay valve device I11, pipe I16, and the control valve device I111.

Since, however, the control chamber 35 in the relay valve device I14 is charged with fluid under pressure from pipe I at the time that its chamber 36 is supplied with fluid under pressure from pipe 239, said relay valve device I14 will assume its position connecting pipe I15 to the vented pipe I13, whereupon fluid under pressure from its control chamber and from the chamber I58 in actuator I55 will flow to atmosphere by way of the pipe I15, communication I95 in said relay valve device I14, the pipe I13, communication I96 30 in the relay valve device I12, the pipe I II, and the control valve device I19.

With fluid under pressure thus released from its chamber I58 and with its chamber I59 also void of fluid under pressure, the jaw clutch actuator I55 will assume its neutral position causing disenga ement of the low speed jaw clutch I31 along with the high speed jaw clutch I38 which remains disengaged.

It will be appreciated that with one or the other of the friction clutches I 98, I61 engaged and with the high speed jaw clutch I38 engaged, said high speed jaw clutch may be disengaged in manner substantially similar to the above through movement of handle I3I on the jaw clutch control valve device I10 from its High speed position to its Neutral position. At completion of such disengagement all parts of the apparatus will assume positions identical to positions assumed after completion of disengagement of the low speed jaw clutch I31 above described. Due to such similarity and for sake of brevity such disengagement of the high speed jaw clutch I38 with one or the other of the friction clutches I96, I91 engaged will not be described.

Summary It will now be seen that I have provided a fluid pressure control apparatus for controlling the operation of an engine power package comprising a plurality of power units such as a pair of internal combustion engines and a multiple speed transmission.

The control apparatus comprises means for effecting regulation of speed of the two engines independently when so employed and means for effecting compounding of their outputs as well as simultaneously effecting synchronous control of their throttle or governor position.

The control apparatus further comprises means for controlling selective engagement and disengagement of a pair of jaw clutches arranged in series with a pair of friction clutches comprised in the multiple speed transmission adapted to be driven by one or both of the internal combustion engines.

According to the invention, the control apparatus is operable to effect engagement and disengagement of either of the friction clutches when the transmission is operating at any speed with one or the other of the jaw clutches engaged. The friction clutches may not be engaged when the jaw clutches are disengaged. The jaw clutches may be engaged and disengaged only at a low speed so that means are provided the control apparatus which operate automatically to effect disengagement of whichever one of the friction clutches may be engaged and to effect application of a braking force for slowing down the transmission when a change in engagement of the jaw clutches is called for by position of an operators handle of a jaw clutch control valve device. When the transmission is thus slowed down to a predetermined low speed (substantially stopped), the control apparatus will automatic-ally efiect the desired change in engagement of the jaw clutches as dictated by the previously positioned handle of jaw clutch control valve device, and at the same time will automatically efiect reengagement of the friction clutch.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In combination, a power input shaft, a

power output shaft, differential speed power transmitting means connecting said shafts for driving said output shaft at different speeds relative to said input shaft comprising two positive type clutches associated with said output shaft and means including two friction clutches connecting said input shaft to each of said positive clutches, a first clutch control device for selectively engaging and disengaging either of said positive clutches, a second clutch control device having different clutch engaging positions for selectively engaging either of said friction clutches and also having a position for disengaging said friction clutches, and means responsive to operation of said first control means, with said second control means in either of said different clutch engaging positions, to effect disengagement and engagement of the respective friction clutch before and after, respectively, disengagement and engagement of said positive clutches.

2. In combination, a power input shaft, a power output shaft, a positive clutch operable by fluid under pressure to drive said output shaft, a friction clutch operable by fluid under pressure to transmit power from said input shaft to said positive clutch, control means for supplying and releasing fluid under pressure for controlling said positive clutch, a fluid pressure controlled relay device for supplying fluid under pressure to operate said friction clutch and for also releasing such fluid under pressure, and means responsive to operation of said control means for varying the pressure of fluid in said relay device in such a manner as to disengage said friction clutch ahead of said positive clutch and for engaging said friction clutch after engaging said positive clutch.

3. In combination, a power input shaft, a power output shaft, a positive clutch for driving said output shaft, a motor operable by fluid under pressure to render said clutch effective and upon release of such fluid under pressure to render said clutch ineffective, friction clutch means operable by fluid under pressure to transmit power from said input shaft to said positive clutch to drive said output shaft and rendered ineffective upon release of such fluid under pressure, control means for supplying fluid under pressure to and for releasing fluid under pressure from said motor, a relay device operable by fluid under pressure to establish a fluid pressure vent from said friction clutch means, and operable upon release of fluid under pressure to supply fluid under pressure to said friction clutch means, and means operative in response to supply and release of fluid under pressure by said control means to release and supply, respectively, fluid under pressure to and from said relay device.

4. In combination, a power input shaft, a power output shaft, a positive clutch for driving said output shaft, a motor operable by fluid under pressure to render said clutch effective and upon release of such fluid under pressure to render said clutch ineffective, friction clutch means operable by fluid under pressure to transmit power from said input shaft to said positive clutch to drive said output shaft and rendered ineffective upon release of such fluid under pressure, control means for supplying fluid under pressure to and for releasing fluid under pressure from said motor, a relay device operable by fluid under pressure to establish a fluid pressure vent from said friction clutch means, and operable upon release of fluid under pressure to supply fluid under pressure to said friction clutch means,

32 means for restricting said supply of fluid uri der pressure to said friction clutch means, and means operative in response to supply and release of fluid under pressure by said control means to release and supply, respectively, fluid under pressure to and from said relay device.

5. In a fluid pressure control apparatus for controlling operation of a transmission comprising an input shaft adapted to be driven by power means, an output shaft for power take-off, friction clutch means and positive clutch means operable into engagement upon supply of fluid under pressure thereto, respectively, and into disengagement upon release of fluid under pressure therefrom, respectively, and means for connecting said friction and positive clutch means in series for operatively connecting said input shaft to said output shaft, in combination, a first control valve device having a first fluid pressure operating connection with said friction clutch means and operable to effect supply of fluid under pressure thereto and release of fluid under pressure therefrom, a second control valve device having a second fluid pressure operating connection with said positive clutch means and operable to effect supply of fluid under pressure thereto and release of fluid under pressure therefrom, and interlock means operable in response to reduction in pressure of fluid in said second fluid pressure operating connection to establish communication between said first operating connection and atmosphere.

6. The combination with power means, a power delivery shaft, fluid pressure actuated friction and positive clutch means having respective driving and driven elements arranged in series for operatively connecting and disconnecting said power means to said delivery shaft, and braking means operatively connected to the driving element of said positive clutch means, of control means for effecting engagement and disengagement of said positive clutch means, and means controlled by said control means for effecting engagement and disengagement of said friction clutch means and for effecting release and application of said braking means, respectively.

7. The combination with power means, apower delivery shaft, fluid pressure actuated friction and positive clutch means having respective driving and driven elements arranged in series for operatively connecting said power means to said power delivery shaft, and braking means operable to effect braking of the driving element of said positive clutch means, of control means for effecting engagement and disengagement of said positive clutch means, means controlled by said control means for effecting engagement and disengagement of said friction clutch means and release and application of said braking means, respectively, and means operable in response to speed of rotation of said delivery shaft to render said positive clutch means non-responsive to dictates of said control means when said shaft is rotating at a speed above a certain value and to render said positive clutch means responsive to dictates of said control means when said shaft is rotating at a speed below said certain value.

8. The combination with power means, speed control means for said power means, a power delivery shaft, and fluid pressure actuated friction and positive clutch means arranged in series for operatively connecting said power means to said power delivery shaft, of control means for effecting engagement and disengagement of said positive clutch means, means controlled by said control means for effecting engagement and disengagement of said friction clutch means, and means responsive to speed of rotation of said delivery shaft to render said positive clutch means non-responsive and responsive to dictates oflsaid control means when said shaft is rotating at speeds above and below a certain minimum value, respectively.

9. The combination with power means, a power delivery shaft, an intermediate shaft, first and second friction clutch means each operable to effect driving connection between said power means and said intermediate shaft, and first and second positive clutch means each operable to effect driving connection between saidintermediate shaft and said delivery shaft, of first control means for effecting engagement and disengagement of said first and second friction clutch means selectively, second control means for effecting engagement and disengagement of said first and second positive jaw clutch means, interlock means controlled by said second control means for rendering said first control means inefiective when said second controlmeans is operated, and means responsive to speed of rotation of said delivery shaft to render said positive clutch means and interlock means responsive and non-responsive, respectively, to dictates of said second control means when said shaft is rotating at a speed below a certain minimum value.

10. The combination with power means, speed contro1 means for said power means, a power delivery shaft, friction clutch means and positive clutch means each having respective driving'and driven elements and each operable into engagement upon supply of fluid under pressure thereto and into disengagement upon release of fluid under pressure therefrom, the driving element of said positive clutch having anoperable connection with the driven element of said friction clutch, and a fluid pressure supply pipe adapted to be connected to a source of fluid under pressure, of first relay valve means operable in response to supply of fluid under pressure to a first control pipe to establish a communication between said friction clutch means and atmosphere and in response to release of fluid under pressure from said control pipe to establish a first communication between said friction clutch means and said supply pipe, a first fluid pressure conduit, control valve means operable manually to one position for effecting supply of fluid under pressure to said first fluid pressure conduit and to another position for effecting release of fluid under pressure from said first fluid pressure conduit, a second fluid pressure conduit, second relay valve means having a control chamber and operable in response to supply of fluid under pressure to its control chamber to connect said first fluid pressure conduit to said second fluid pressure conduit and operable in response to release of fluid under pressure from its control chamber to disconnect said first fluid pressure conduit from said second fluid pressure conduit and to connect said second fluid pressure conduit to atmosphere, a first double check valve having one inlet connected to said second fluid pressure conduit, another inlet, and also having an outlet connected to the control chambe of said second relay valve means, a third fluid pressure conduit connected to said positive'clutch means, third relay valve means having a control chamber connected to said third fluid pressure conduit and having another fluid pressure chamber and being operabie when its control chamber and fluid pressurechamber are either both void of fluid under pressure or charged with fluid under pressure to establish communication between said third fluid pressure conduit and said second fluid pressure conduit and operable when its fluid pressurechamber is void of fluid under pressure and its control chamber is charged with fluid under pressure to establish communication between said third fluid pressure conduit and said supply pipe, fourthrel-ay valve means responsive upon supply of fluid under pressure to said second fluid pressureconduit to establish a fourth communi-cation'between said first control pipe and atmosphere and upon release of fluid under pressure from said second fluid pressure conduit to establish communication between said first control pipe and said supply pipe, a second control pipe connected to said fluid pressure chamber in said third. relay valve means and to said other outlet in said double heck valve, fifth relay valve means operable in response to supply of fluid under pressure to a third control pipe to establish communication between said first control pipe and said second control pipe and operable in response to release of fluid under pressure from said third control pipe to establish a fifth communication between said second control pipe and atmosphere, governor means responsive to speed of rotation of said delivery shaft and operable at speeds above a certain minimum value to establish a vent from said third control pipe to atmosphere and at speeds below said certain minimum value to .disestablish said vent, and a restricted communication connecting said third control pipe to saidlfirst control pipe.

11. In a fluid pressure control apparatus for controlling operation of a transmission comprising an input shaft adapted to be driven by power means, an output shaft for power take-off, friction clutch means and positive clutch means operable into engagement upon supply of fluid under pressure thereto, respectively, and into disengagement upon release of fluid under pressure therefrom, respectively, said friction and positive clutch means being connected in series for operatively connecting said input shaft to said output shaft, in combination, a first control valve device having a first fluid pressure operating connection with said friction clutch means and operable to effect supply of fluid under pressure thereto and release of fluid under pressure therefrom, a second control valve device having a second fluid pressure operating connection with said positive clutch means and operable to effect supply of fluid under pressure thereto and release of fluid under pressure therefrom, and interlock means operable in response to reduction in pressure of fluid in said second fluid pressure operating connection to establish communication between said first operating connection and atmosphere, and choke means in said communication.

12. In combination, a power input shaft, a power output shaft, two positive clutches each for driving said output shaft, means including a friction clutch for selectively driving said positive clutches, braking means for said output shaft, an operators control device comprising a control lever having one position for rendering one of said positive clutches effective to drive said output shaft and the other ineffective and having a second position for renderin said other positive clutch effective and said one ineffective, interlock means operable upon movement of said lever from either one of its two positions to the other to effect operation of said braking means and disengagement of said friction clutch, speed responsive means responsive to speed of rotation of said output shaft, and means included in said interlock means controlled by said speed responsive means and operable upon reduction in said speed to a chosen low degree to effect engagement of the positive clutch corresponding to the position of said control lever, disengagement of the other positive clutch, release of said braking means and engagement of said friction clutch.

13. In combination, a power input shaft, a power output shaft, two positive clutches each for driving said output shaft, means including a friction clutch for selectively driving said positive clutches, braking means for said output shaft, an operators control device comprising a control lever having two positions corresponding to selective engagement of said two positive clutches, interlocking means responsive to movement of said lever from either one of its two positions to the other to effect operation of said braking means, and to disengage said friction clutch, means included in said interlock means controlled by speed of rotation of said output shaft and operative upon a reduction in such speed to a chosen low degree to effect operation of said interlock means to engage the positive clutch corresponding to the position of said control lever, to release said braking means and means to engage said friction clutclumeans for delaying release of said braking means and engagement of said friction clutch with respect to engagementv of the positive clutch, and means for delaying engagement of said friction clutch. 14. In combination with a fluid pressure supply pipe adapted to be connected to a source of fluid under pressure, of a pair of serially arranged clutch means each engaged by supply of fluid under pressure thereto and disengaged by release of fluid under pressure therefrom, one control' means having a. fluid pressure inlet operable manually to selectively establish connection 'of one of said clutch means to either said inlet or to atmosphere, and other control means operable manually to effect connection of the other of said clutch means and connection of said inlet selectively to either said supply pipe or to atmosphere.

15. The combination as set forth in claim 10, including fluid pressure braking means operable in response to supply and release of fluid under pressure to and from said first control pipe to establish and disestablish, respectively, restraint to rotation of the driving element of said positive cluch means.

16. The combination as set forth in claim 10, including fluid pressure braking means operable in response to supply and release of fluid under pressure to and from said first control pipe to establish and disestablish, respectively, restraint to rotation of the driving element of said positive clutch means, and means restricting flow of fluid under pressure through said first communication, said fourth communication, and said flfth communication.

ROY R. STEVENS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,476,989 Massey Dec. 11, 1923 1,634,489 Cartlidge July 5, 1927 2,050,520 Carter Aug. 11, 1936 2,077,553 Fishburn et a1 Apr. 20, 1937 2,482,274 Hewitt et a1. Sept. 20, 1949 OTHER REFERENCES Ser. No. 400,817, K. Maybach (A. P. C.) pub.

May 18, 1943. 

